The P300 event related potential component in the diagnosis of dementia

Several studies have suggested that delays in the latency of the P300 ERP component are highly sensitive and specific to dementia and that ERP measurements may become a useful clinical tool in aiding diagnosis. This study examines the sensitivity of P300 measurements to dementia and addresses several methodological issues that limit previous research. Twenty-four patients with dementia diagnosed according to ICD-10 criteria were compared with 100 normal controls, 31 of whom were older than 60. An auditory oddball paradigm was employed to elicit the P300. Mean P300 latency did not differ significantly between the two groups. When individual subjects were examined only 13% of patients with dementia fell outside the two standard error band of the regression of P300 latency on age derived from controls. Thus, this study has not demonstrated clinically useful abnormalities of the P300 component in dementia.

Computerized axial tomographic reconstruction of coronary tree cross sections from a small number of cineradiographic views

Three-dimensional reconstruction of the coronary tree from a conventional cineangiographic study is limited, in part, by the small number of available cineangiographic views. The potential utility of a maximum entropy iterative algorithm (MENT) for reconstruction of myocardial planes perpendicular to the axis of cineangiographic rotation from a small number (n = 6-18) of cineangiographic views was tested in vitro. The coronary arteries of postmortem human, canine, and calf hearts were filled with a silicone/thorium oxide mold to simulate in vivo angiographic contrast. Thirty-five-millimeter cineradiographs of each heart were obtained at 10 degrees intervals over 180 degrees about a myocardial central axis of rotation under exposure conditions which simulated the clinical setting. Projection data were derived from cinedensitometric scans across the entire myocardial shadow, perpendicular to the axis of rotation in each view, after 512 X 512 digitization with a vidicon camera/digitizer interfaced to a VAX computer. Comparison of MENT-reconstructed images with corresponding anatomic myocardial cross sections indicate that as few as 6 to 12 views can be used to reconstruct the cross sections of the multiple coronary branches (n = 6-11) within a plane of reconstruction.

Microanalysis of the amino-acid sequence of monomeric beta-lactoglobulin I from donkey (Equus asinus) milk. The primary structure and its homology with a superfamily of hydrophobic molecule transporters

The complete primary structure of donkey beta-lactoglobulin I was determined by pulsed-liquid phase microsequencing of tryptic peptides. The protein has been isolated in monomeric form and it corresponds to monomeric beta-lactoglobulin of type I. With the inclusion of donkey beta-lactoglobulin I there are 13% common residues amongst the members of the beta-lactoglobulin family. Donkey beta-lactoglobulin I is homologous to the retinol-binding protein, bilin-binding protein and five other proteins belonging to the new superfamily of hydrophobic molecule transporters. A rapid method for peptide isolation and the strategy for microsequencing of this protein have been described.

Laser balloon angioplasty: effect of constant temperature versus constant power on tissue weld strength

Thermal fusion of intimal plaque with the arterial wall during coronary balloon angioplasty may significantly reduce the incidence of abrupt closure and may reduce the occurrence of delayed restenosis by improvement of luminal size and shape. Although Nd:YAG laser energy has been shown to be effective in the thermal fusion of plaque-arterial wall separations in vitro, the most efficient manner of energy delivery for rapid achievement of therapeutically useful equilibrium tissue temperature during laser exposure has not been defined. A comparison of weld strength achieved was therefore made between two formats of laser delivery: constant power vs. decremental power with an initial high dose followed by the minimal serial decrements necessary to maintain tissue temperature constant for 15 seconds. One hundred sixty-six tissue discs of human postmortem aorta of 11 mm diameter were studied. Intimal plaque was separated from the media, the two layers were juxtaposed, a force of 4 pounds was applied, and a fiberoptic-delivered laser beam was directed perpendicular to the tissue over a 3-mm-diameter nominal spot size. Weld strength was measured as the shear force required to separate completely the two tissue layers. The mean weld strength (75 g) achieved by use of the decremental power format was significantly higher (P less than .01) than the mean strength (32 g and 56 g) achieved by using constant power for 20 and 30 seconds, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

L-carnitine treatment in the hyperlipidemic rabbit

A study was designed to examine the hypolipidemic effect of L-carnitine treatment (4 weeks, 170 mg/kg/d) in rabbits fed a high fat diet (5% corn oil/0.5% cholesterol, w/w). Eight weeks of exposure to the high fat diet significantly increased plasma total cholesterol and triglycerides. VLDL associated triglycerides, cholesterol, apo-B, and total protein were also significantly increased with the diet. There was no change in HDL-cholesterol levels. Plasma concentration of carnitine (free, acyl, and total) all increased significantly with the high fat diet. The content of free, short-chain, and total carnitine were decreased in the liver whereas the content of long-chain acylcarnitines was increased. The diet generated a significant steatosis within the livers of these animals. Four weeks of treatment of L-carnitine reduced the extent of the liver steatosis and significantly decreased plasma total cholesterol, triglycerides, VLDL associated triglycerides, cholesterol, and total protein. HDL-cholesterol levels were unaffected by the treatment. All plasma fractions of carnitine (free, acetyl, acyl, and total) were significantly increased above those levels seen after 8 weeks of the high fat diet alone. The content of liver carnitine and its esters was normalized following treatment. The high fat diet decreased liver HMG-CoA reductase activity and increased the activities of 7-alpha-hydroxylase and acylcholesterol acyltransferase (ACAT). L-Carnitine treatment blunted the magnitude of the diet induced increase in 7 alpha-hydroxylase activity, yet overall the activity still remained elevated relative to controls. ACAT activity increased (1.5 times) with the high fat diet and increased further (4.5 times) following carnitine treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Evoked response potentials and regional cerebral blood flow in somatization disorder

Somatization disorder (SMD) is a chronic condition characterized by multiple complaints which are not due to any apparent organic illness but frequently involve pain. This study employs computer-aided imaging technologies to examine brain function in thousandths of a second (event-related brain potentials) and over a number of minutes (regional cerebral blood flow). Fourteen patients with SMD and 14 normal controls were investigated. Results from both studies suggest that patients with SMD have a dysfunction in the processes of attention, compared to normal controls.

L-carnitine treatment in glutaric aciduria type I

Patients with organic aciduria may have a higher than normal requirement for L-carnitine. In a patient with type I glutaric aciduria, serum total L-carnitine levels were 8.5 microM (normal, 54.4 +/- 14.2 [2 SD] microM). After treatment with L-carnitine for 1 month, serum levels of both free and total L-carnitine were normal with an acyl-to-total ratio of 0.18. The fractional clearance rates of free and acylcarnitine were increased fourfold by treatment. Acetylcarnitine accounted for a lower than normal percentage of acylcarnitine recovered in serum and urine. Data suggest that this patient may have been carnitine-deficient.

Hemoglobin alpha chain deficiency in black children with variable quantities of hemoglobin Bart's at birth

Hematologic and globin chain synthesis studies have been made in 21 children, aged 2 to 6 years, many of their parents, and several normal adults and alpha-thalassemia heterozygotes. At birth, 11 children had about 5% hemoglobin (Hb) Bart's, 5 had about 2% Hb Bart's, and 5 had no trace of Hb Bart's. A significant decrease in mean corpuscular volume. (MCV) and mean corpuscular hemoglobin (MCH) values and an increase in the beta/alpha ratio was observed in the first group; microcytosis and hypochromia were absent in the children of the second group although the beta/alpha ratio was significantly increased. The alpha chain deficiency is familial. Increased alpha/alpha ratios were present in many parents although only two parents of children with 5% Hb Bart's at birth had hematologic findings suggestive of the presence of the same type of defect as observed in the children with the larger amount of Hb Bart's at birth.

Oxalate (Halogeton) poisoning of sheep: certain physiopathologic changes

Certain clinical changes associated with acute oxalate (halogeton) poisoning were determined in sheep given (by stomach tube into the rumen) a lethal dose of Halogeton glomeratus. Plasma concentrations of calcium and calcium ion activity decreased over several hours to such low levels that tetany or coma occurred and death followed. Cerebrospinal fluid concentrations of calcium did not reflect the degree of hypocalcemia. In 2 pregnant sheep administered halogeton, the plasma concentration of calcium in the fetus did not decrease despite the appearance of severe maternal hypocalcemia. Increases in plasma total inorganic phosphate and magnesium concentrations occurred as the hypocalcemia progressed. Hyperglycemia was often marked as hypocalcemia became severe; however, as hyperglycemia increased, plasma immunoreactive insulin concentrations remained inappropriately low in relation to the plasma concentration of glucose. Intravenous infusion of a calcium solution at this time was associated with marked increase in immunoreactive insulin concentration and a decrease in glucose concentration. Ruminal activity, as measured by frequency and amplitude of contractions of the rumen, was greatly reduced as hypocalcemia progressed. Seemingly, body temperature became lowered as severity of the hypocalcemia progressed. Seemingly, body temperature became lowered as severity of the hypocalcemia increased, as determined by intramuscularly or intraperitoneally implanted temperature telemetry devices. However, the occurrence of tetany and the fleece covering could either modify or reverse this decrease in body temperature.

Effect of treadmill exercise on asthmatic children

Measurement of peak expiratory flow rate before and after treadmill walking repeated at hourly intervals in asthmatic children disclosed progressive decreases in exercise-induced asthma. Treadmill running was followed by more extreme excercise-induced bronchospasm than treadmill walking. Exercise-induced asthma occurred in some children whose heart rates did not reach 160 during treadmill exercise, and heart rate during exercise was not correlated with the extent of exercise-induced bronchospasm.

Temporal perspectives and alienation

Time perspectives were studied for 2 groups of alienated students. From the discrepancy berween own values and the perceived values of Western culture it was found that Ss who attributed greater conservatism to their culture (radical alienation) were significantly more oriented to the present than Ss attributing greater radicalism to their culture (conservative alienation), while the latter group were significantly more oriented to personal and historical past.